Internal combustion engines are widely used for powering vehicles. Internal combustion engines include an intake manifold for receiving and directing air to a throttle, wherein the air is mixed with fuel and introduced into a cylinder and piston arrangement for combustion. The combustion causes reciprocating movement of the piston, which in turn is converted to torque usable for moving the vehicle. The products of the combustion are then expelled through an exhaust.
Supercharger and turbocharger systems (chargers) are commonly used for increasing the torque or power output of the engine. Chargers basically increase the pressure and density in the intake manifold. The increased pressure and density of air provided by the charger allows more fuel to be ignited, which results in a more powerful combustion stroke in the engine's cylinders. Superchargers are mechanically driven by the vehicle crankshaft, while turbochargers are driven by a flow of exhaust gases. Conventional charger systems, however, are typically continuously operative while the engine is running.
Accordingly, it remains desirable to provide an intake system that provides enhanced efficiency by allowing ambient operation of the engine during light loading conditions and super- or turbo-charged operation of the engine under heavy loading conditions.